Typically, two people are required to confirm that all of the exterior lighting on the trailer works correctly. A first person is within the passenger compartment and activates the lights on the vehicle, which in turn activate the respective lights on the trailer. A second person walks around the perimeter of the trailer to confirm that each of the lights on the vehicle are activating the respective lights on the trailer. By walking around the trailer and individually identifying each of the lights, the second person who is outside of the vehicle is able to communicate to the first person inside the vehicle which lights on the trailer are not illuminated.